/* =====================================================================
   ZUS Coffee CEO Latte — Microeconomics Portfolio
   css/styles.css
   Design: Editorial Luxury · Dark Espresso · Amber Accent
   ===================================================================== */

/* ─────────────────────────────────────────
   1. DESIGN TOKENS
───────────────────────────────────────── */
:root {
  /* Colours */
  --c-base:           #0D0B08;
  --c-surface:        #141210;
  --c-surface-2:      #1C1916;
  --c-surface-3:      #242018;
  --c-surface-4:      #2C2820;
  --c-accent:         #C9893A;
  --c-accent-light:   #E8A84E;
  --c-accent-deep:    #7A4D1A;
  --c-accent-muted:   rgba(201, 137, 58, 0.18);
  --c-text-primary:   #F2EDE8;
  --c-text-secondary: #A89B8A;
  --c-text-tertiary:  #6E6257;
  --c-border:         rgba(201, 137, 58, 0.14);
  --c-border-subtle:  rgba(242, 237, 232, 0.07);
  --c-border-card:    rgba(201, 137, 58, 0.10);
  --c-red-tint:       rgba(180, 68, 68, 0.12);
  --c-red-text:       #E07070;
  --c-green-tint:     rgba(56, 160, 108, 0.12);
  --c-green-text:     #5EC99A;

  /* Shadows (amber-tinted, layered) */
  --shadow-card:     0 1px 2px rgba(0,0,0,0.35), 0 4px 16px rgba(0,0,0,0.45), 0 0 0 1px rgba(201,137,58,0.07);
  --shadow-hover:    0 2px 4px rgba(0,0,0,0.35), 0 8px 32px rgba(0,0,0,0.5), 0 0 0 1px rgba(201,137,58,0.14), 0 0 24px rgba(201,137,58,0.06);
  --shadow-floating: 0 4px 12px rgba(0,0,0,0.5), 0 16px 48px rgba(0,0,0,0.6), 0 0 0 1px rgba(201,137,58,0.12);
  --shadow-nav:      0 2px 8px rgba(0,0,0,0.4), 0 8px 24px rgba(0,0,0,0.5), 0 0 0 1px rgba(201,137,58,0.1);
  --shadow-accent:   0 0 20px rgba(201,137,58,0.25), 0 0 60px rgba(201,137,58,0.08);

  /* Typography */
  --font-display: 'Playfair Display', Georgia, serif;
  --font-body:    'DM Sans', system-ui, sans-serif;
  --font-mono:    'DM Mono', 'Courier New', monospace;

  /* Spacing tokens */
  --sp-1:  0.25rem;
  --sp-2:  0.5rem;
  --sp-3:  0.75rem;
  --sp-4:  1rem;
  --sp-5:  1.25rem;
  --sp-6:  1.5rem;
  --sp-8:  2rem;
  --sp-10: 2.5rem;
  --sp-12: 3rem;
  --sp-16: 4rem;
  --sp-20: 5rem;
  --sp-24: 6rem;
  --sp-32: 8rem;

  /* Border radius */
  --r-sm:   0.25rem;
  --r-md:   0.5rem;
  --r-lg:   0.875rem;
  --r-xl:   1.25rem;
  --r-2xl:  1.75rem;
  --r-full: 9999px;

  /* Easing */
  --ease-spring: cubic-bezier(0.32, 0.72, 0, 1);
  --ease-out:    cubic-bezier(0, 0, 0.2, 1);
  --ease-in:     cubic-bezier(0.4, 0, 1, 1);

  /* Z-index scale */
  --z-base:    0;
  --z-raised:  10;
  --z-overlay: 40;
  --z-nav:     80;
  --z-menu:    90;
  --z-grain:   100;
}

/* ─────────────────────────────────────────
   2. RESET & GLOBALS
───────────────────────────────────────── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--c-base);
  color: var(--c-text-secondary);
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  user-select: none;
  cursor: default;
  overflow-x: hidden;
}

body.menu-open {
  overflow: hidden;
}

/* Allow selection on interactive and content elements */
a, button, input, textarea, select,
p, li, td, th, h1, h2, h3, h4, h5, h6,
.reference-list, .objectives-list {
  user-select: text;
  cursor: auto;
}

a, button { cursor: pointer; }

img, svg { display: block; max-width: 100%; }

ul, ol { list-style: none; }

strong { font-weight: 600; }

.accent { color: var(--c-accent); }
.mono   { font-family: var(--font-mono); }

/* ─────────────────────────────────────────
   3. GRAIN OVERLAY
───────────────────────────────────────── */
.grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: var(--z-grain);
  opacity: 0.04;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  background-size: 256px 256px;
}

/* ─────────────────────────────────────────
   4. SKIP LINK
───────────────────────────────────────── */
.skip-link {
  position: absolute;
  top: -100%;
  left: var(--sp-4);
  background: var(--c-accent);
  color: var(--c-base);
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 600;
  padding: var(--sp-2) var(--sp-4);
  border-radius: var(--r-md);
  text-decoration: none;
  z-index: 9999;
}

.skip-link:focus {
  top: var(--sp-4);
}

/* ─────────────────────────────────────────
   5. CONTAINER
───────────────────────────────────────── */
.container {
  width: 100%;
  max-width: 1200px;
  margin-inline: auto;
  padding-inline: var(--sp-6);
}

/* ─────────────────────────────────────────
   6. NAVBAR
───────────────────────────────────────── */
#navbar {
  position: fixed;
  top: 0.75rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: var(--z-nav);
  pointer-events: none;
  width: auto;
}

.nav-island {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-6);
  width: max-content;
  max-width: calc(100vw - 3rem);
  background: rgba(20, 18, 16, 0.82);
  backdrop-filter: blur(20px) saturate(1.4);
  -webkit-backdrop-filter: blur(20px) saturate(1.4);
  border: 1px solid var(--c-border);
  border-radius: var(--r-full);
  padding: var(--sp-4) var(--sp-8);
  box-shadow: var(--shadow-nav);
  pointer-events: all;
  transition: background 0.4s var(--ease-out),
              box-shadow 0.4s var(--ease-out);
}

#navbar.scrolled .nav-island {
  background: rgba(13, 11, 8, 0.92);
  box-shadow: var(--shadow-floating);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  text-decoration: none;
  flex-shrink: 0;
}

.brand-title {
  font-family: var(--font-display);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--c-text-primary);
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.brand-sep {
  color: var(--c-text-tertiary);
  font-size: 0.85rem;
}

.brand-org {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--c-accent);
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.nav-links {
  display: none;
  align-items: center;
  gap: var(--sp-1);
}

.nav-link {
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--c-text-secondary);
  text-decoration: none;
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--r-full);
  white-space: nowrap;
  position: relative;
  transition: color 0.25s var(--ease-out),
              background 0.25s var(--ease-out);
}

.nav-link:hover {
  color: var(--c-text-primary);
  background: var(--c-accent-muted);
}

.nav-link:focus-visible {
  outline: 2px solid var(--c-accent);
  outline-offset: 2px;
}

.nav-link.active {
  color: var(--c-accent-light);
  background: var(--c-accent-muted);
}

/* Hamburger */
.hamburger {
  display: flex;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  padding: var(--sp-2);
  border-radius: var(--r-md);
  position: relative;
  width: 36px;
  height: 36px;
  align-items: center;
  justify-content: center;
}

.hamburger:focus-visible {
  outline: 2px solid var(--c-accent);
  outline-offset: 2px;
}

.hamburger-bar {
  display: block;
  width: 20px;
  height: 1.5px;
  background: var(--c-text-secondary);
  border-radius: var(--r-full);
  position: absolute;
  transition: transform 0.35s var(--ease-spring),
              opacity 0.25s var(--ease-out);
}

.hamburger-bar:first-child { transform: translateY(-4px); }
.hamburger-bar:last-child  { transform: translateY(4px); }

.hamburger.is-open .hamburger-bar:first-child {
  transform: rotate(45deg) translateY(0);
  background: var(--c-accent);
}

.hamburger.is-open .hamburger-bar:last-child {
  transform: rotate(-45deg) translateY(0);
  background: var(--c-accent);
}

/* ─────────────────────────────────────────
   7. MOBILE MENU
───────────────────────────────────────── */
.mobile-menu {
  position: fixed;
  inset: 0;
  background: rgba(10, 8, 6, 0.96);
  backdrop-filter: blur(24px) saturate(1.2);
  -webkit-backdrop-filter: blur(24px) saturate(1.2);
  z-index: var(--z-menu);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.35s var(--ease-out);
}

.mobile-menu.is-open {
  opacity: 1;
  pointer-events: all;
}

.mobile-menu nav ul {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-2);
}

.mobile-nav-link {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: 600;
  color: var(--c-text-primary);
  text-decoration: none;
  padding: var(--sp-3) var(--sp-6);
  display: block;
  text-align: center;
  opacity: 0;
  transform: translateY(16px);
  transition: opacity 0.45s var(--ease-out),
              transform 0.45s var(--ease-spring),
              color 0.2s var(--ease-out);
}

.mobile-menu.is-open .mobile-nav-link {
  opacity: 1;
  transform: translateY(0);
}

.mobile-menu.is-open li:nth-child(1) .mobile-nav-link { transition-delay: 0.06s; }
.mobile-menu.is-open li:nth-child(2) .mobile-nav-link { transition-delay: 0.1s; }
.mobile-menu.is-open li:nth-child(3) .mobile-nav-link { transition-delay: 0.14s; }
.mobile-menu.is-open li:nth-child(4) .mobile-nav-link { transition-delay: 0.18s; }
.mobile-menu.is-open li:nth-child(5) .mobile-nav-link { transition-delay: 0.22s; }

.mobile-nav-link:hover  { color: var(--c-accent-light); }
.mobile-nav-link:focus-visible { outline: 2px solid var(--c-accent); outline-offset: 2px; }

.mobile-menu-footer {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--c-text-tertiary);
  letter-spacing: 0.06em;
  text-align: center;
  margin-top: var(--sp-10);
  opacity: 0;
  transition: opacity 0.5s 0.3s var(--ease-out);
}

.mobile-menu.is-open .mobile-menu-footer { opacity: 1; }

/* ─────────────────────────────────────────
   8. SECTION BASE
───────────────────────────────────────── */
.section {
  padding-block: var(--sp-24);
  position: relative;
}

.section--intro {
  background-color: transparent;
  padding-block: 0;
}

.section--alt {
  background-color: var(--c-surface);
}

.section--findings {
  background-color: var(--c-base);
}

.section--references {
  background-color: var(--c-surface);
}

.section-body {
  padding-block: var(--sp-20);
}

/* ─────────────────────────────────────────
   9. TYPOGRAPHY — HEADINGS & EYEBROWS
───────────────────────────────────────── */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  color: var(--c-text-primary);
  line-height: 1.12;
  letter-spacing: -0.03em;
}

h1 {
  font-size: clamp(2.4rem, 5.5vw, 4.5rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.06;
}

h1 em {
  font-style: italic;
  color: var(--c-accent);
}

h2 {
  font-size: clamp(1.8rem, 3.5vw, 2.8rem);
  font-weight: 700;
  letter-spacing: -0.035em;
}

h3 {
  font-size: clamp(1.2rem, 2.2vw, 1.6rem);
  font-weight: 600;
  letter-spacing: -0.025em;
}

h4 {
  font-size: 1rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.3;
}

p {
  font-size: 0.94rem;
  line-height: 1.75;
  color: var(--c-text-secondary);
}

.eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--c-accent);
  background: var(--c-accent-muted);
  border: 1px solid var(--c-border);
  border-radius: var(--r-full);
  padding: var(--sp-2) var(--sp-4);
}

.eyebrow--sm {
  font-size: 0.63rem;
  padding: 0.2rem var(--sp-3);
}

.section-header {
  margin-bottom: var(--sp-12);
}

.section-header h2 {
  margin-top: var(--sp-4);
}

.section-header--tight {
  margin-top: var(--sp-12);
  margin-bottom: var(--sp-8);
}

.section-intro {
  max-width: 680px;
  margin-top: var(--sp-5);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--c-text-secondary);
}

.subsection-header {
  display: flex;
  align-items: baseline;
  gap: var(--sp-4);
  margin-top: var(--sp-16);
  margin-bottom: var(--sp-8);
  padding-bottom: var(--sp-4);
  border-bottom: 1px solid var(--c-border-subtle);
}

.subsection-num {
  font-size: 0.72rem;
  font-weight: 500;
  color: var(--c-accent);
  letter-spacing: 0.06em;
  flex-shrink: 0;
}

.subsection-header h3 {
  font-size: clamp(1.1rem, 2vw, 1.45rem);
}

/* ─────────────────────────────────────────
   10. HERO SECTION
───────────────────────────────────────── */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding-top: 6rem;
  padding-bottom: 4rem;
  overflow: hidden;
}

.hero-video {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 0;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 50% at 20% 30%, rgba(201,137,58,0.07) 0%, transparent 60%),
    radial-gradient(ellipse 60% 40% at 80% 70%, rgba(201,137,58,0.04) 0%, transparent 55%),
    linear-gradient(to bottom, rgba(0,0,0,0.15) 0%, rgba(0,0,0,0.25) 50%, rgba(0,0,0,0.65) 100%);
  pointer-events: none;
  z-index: 1;
}

.hero .container {
  position: relative;
  z-index: 2;
}

.hero .eyebrow {
  margin-bottom: var(--sp-6);
}

.hero h1 {
  margin-top: var(--sp-6);
  max-width: 820px;
}

.hero-subtitle {
  margin-top: var(--sp-5);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  color: var(--c-text-tertiary);
}

.group-members {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-3);
  margin-top: var(--sp-8);
}

.group-members li {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--c-text-tertiary);
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-subtle);
  border-radius: var(--r-full);
  padding: var(--sp-2) var(--sp-4);
  letter-spacing: 0.02em;
  white-space: nowrap;
  user-select: text;
}

.hero-scroll-hint {
  position: absolute;
  bottom: var(--sp-8);
  left: var(--sp-6);
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: var(--sp-3);
}

.scroll-label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--c-text-tertiary);
  transform: rotate(-90deg) translateX(-50%);
  transform-origin: left center;
  white-space: nowrap;
}

.scroll-line {
  width: 1px;
  height: 48px;
  background: linear-gradient(to bottom, var(--c-accent), transparent);
  animation: scrollPulse 2.4s var(--ease-out) infinite;
}

@keyframes scrollPulse {
  0%   { opacity: 0; transform: scaleY(0); transform-origin: top; }
  50%  { opacity: 1; }
  100% { opacity: 0; transform: scaleY(1); transform-origin: top; }
}

/* ─────────────────────────────────────────
   11. INFO GRID (Cards — double-bezel)
───────────────────────────────────────── */
.info-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-4);
  margin-bottom: var(--sp-8);
}

/* Double-bezel card */
.info-card {
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-card);
  border-radius: var(--r-xl);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.35s var(--ease-out),
              transform 0.35s var(--ease-spring);
}

.info-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.info-card__inner {
  background: var(--c-surface-3);
  border: 1px solid var(--c-border-subtle);
  border-radius: calc(var(--r-xl) - 0.5rem);
  padding: var(--sp-6);
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.04);
}

.info-card__label {
  display: block;
  font-size: 0.65rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--c-accent);
  margin-bottom: var(--sp-3);
}

.info-card__inner p {
  font-size: 0.9rem;
  line-height: 1.72;
}

/* ─────────────────────────────────────────
   12. COMPETITORS BLOCK
───────────────────────────────────────── */
.competitors-block {
  margin-bottom: var(--sp-8);
}

.competitors-block .info-card__label {
  margin-bottom: var(--sp-4);
}

.competitor-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-2);
}

.competitor-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--c-text-secondary);
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-subtle);
  border-radius: var(--r-full);
  padding: var(--sp-2) var(--sp-4);
  letter-spacing: 0.02em;
  transition: border-color 0.2s var(--ease-out),
              color 0.2s var(--ease-out);
}

.competitor-tag:hover {
  color: var(--c-accent-light);
  border-color: var(--c-border);
}

/* ─────────────────────────────────────────
   13. OBJECTIVES LIST
───────────────────────────────────────── */
.objectives-block {
  margin-bottom: var(--sp-8);
}

.objectives-list {
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  margin-top: var(--sp-5);
}

.objectives-list li {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-4);
  padding: var(--sp-4) var(--sp-5);
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-subtle);
  border-radius: var(--r-lg);
  font-size: 0.9rem;
  color: var(--c-text-secondary);
  line-height: 1.6;
  transition: border-color 0.25s var(--ease-out),
              background 0.25s var(--ease-out);
}

.objectives-list li:hover {
  background: var(--c-surface-3);
  border-color: var(--c-border);
}

.obj-num {
  font-size: 0.65rem;
  color: var(--c-accent);
  letter-spacing: 0.06em;
  flex-shrink: 0;
  margin-top: 0.15rem;
}

/* ─────────────────────────────────────────
   14. LIMITATIONS CARD
───────────────────────────────────────── */
.limitations-block {
  margin-bottom: var(--sp-12);
}

.limitations-card {
  background: var(--c-surface-2);
  border: 1px solid rgba(201,137,58,0.12);
  border-radius: var(--r-xl);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
}

.limitations-card__inner {
  background: var(--c-surface-3);
  border: 1px solid var(--c-border-subtle);
  border-radius: calc(var(--r-xl) - 0.5rem);
  padding: var(--sp-6);
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.04);
}

.limitations-card__inner ul {
  list-style: disc;
  padding-left: var(--sp-5);
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
}

.limitations-card__inner li {
  font-size: 0.88rem;
  color: var(--c-text-secondary);
  line-height: 1.65;
  user-select: text;
}

/* ─────────────────────────────────────────
   15. VIDEO PLACEHOLDER
───────────────────────────────────────── */
.video-placeholder {
  margin-block: var(--sp-12);
  background: var(--c-surface-2);
  border: 1px solid var(--c-border);
  border-radius: var(--r-2xl);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
  max-width: 800px;
  margin-inline: auto;
  transition: box-shadow 0.35s var(--ease-out),
              border-color 0.35s var(--ease-out);
}

.video-placeholder:hover {
  box-shadow: var(--shadow-hover);
  border-color: rgba(201,137,58,0.25);
}

.video-placeholder__inner {
  background: var(--c-surface-3);
  border: 1px solid var(--c-border-subtle);
  border-radius: calc(var(--r-2xl) - 0.5rem);
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.04);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--sp-6);
  padding: var(--sp-12) var(--sp-8);
  aspect-ratio: 16 / 9;
  position: relative;
  overflow: hidden;
}

.video-placeholder__inner::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 70% 60% at 50% 50%, rgba(201,137,58,0.05) 0%, transparent 70%);
  pointer-events: none;
}

/* CSS-only play icon */
.video-play-icon {
  width: 64px;
  height: 64px;
  border-radius: var(--r-full);
  background: rgba(201,137,58,0.15);
  border: 1.5px solid var(--c-border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: background 0.25s var(--ease-out),
              transform 0.35s var(--ease-spring);
}

.video-placeholder:hover .video-play-icon {
  background: rgba(201,137,58,0.25);
  transform: scale(1.08);
}

.play-triangle {
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 10px 0 10px 18px;
  border-color: transparent transparent transparent var(--c-accent);
  margin-left: 3px;
}

.video-placeholder__text {
  text-align: center;
  position: relative;
  z-index: 1;
}

.video-label {
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--c-accent);
  margin-bottom: var(--sp-2);
}

.video-title {
  font-family: var(--font-display);
  font-size: clamp(0.95rem, 2vw, 1.2rem);
  font-weight: 600;
  color: var(--c-text-primary);
  margin-bottom: var(--sp-2);
}

.video-note {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--c-text-tertiary);
  letter-spacing: 0.04em;
}

/* ─────────────────────────────────────────
   VIDEO EMBED BLOCKS
───────────────────────────────────────── */
.skit-section {
  background: var(--c-base);
  border-top: 1px solid rgba(201,137,58,0.12);
  border-bottom: 1px solid rgba(201,137,58,0.12);
  padding: var(--sp-16) var(--sp-6);
  text-align: center;
}

.skit-label {
  display: block;
  font-size: 0.65rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--c-accent);
  margin-bottom: var(--sp-3);
}

.skit-subtitle {
  font-family: var(--font-display);
  font-size: clamp(1.2rem, 3vw, 1.8rem);
  font-weight: 600;
  color: var(--c-text-primary);
  margin-bottom: var(--sp-8);
}

.video-embed-block {
  margin-top: var(--sp-6);
}

.video-embed-wrap {
  padding-block: var(--sp-12);
}

.video-embed-wrap video {
  max-width: 860px;
  width: 100%;
  display: block;
  margin-inline: auto;
  border-radius: var(--radius-md);
}

.video-embed-wrap--portrait video {
  max-width: 400px;
}

/* ─────────────────────────────────────────
   16. METHODOLOGY SECTION
───────────────────────────────────────── */
.method-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-4);
  margin-bottom: var(--sp-12);
}

/* Method card — double-bezel */
.method-card {
  background: var(--c-base);
  border: 1px solid var(--c-border-card);
  border-radius: var(--r-xl);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.35s var(--ease-out),
              transform 0.35s var(--ease-spring);
}

.method-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.method-card__inner {
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-subtle);
  border-radius: calc(var(--r-xl) - 0.5rem);
  padding: var(--sp-6);
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.03);
}

.method-card__num {
  font-size: 0.65rem;
  color: var(--c-accent);
  letter-spacing: 0.08em;
  display: block;
  margin-bottom: var(--sp-3);
}

.method-card__inner h3 {
  font-size: 1rem;
  margin-bottom: var(--sp-3);
}

.method-card__inner p {
  font-size: 0.88rem;
  line-height: 1.7;
}

/* Process Steps */
.process-block {
  margin-bottom: var(--sp-10);
}

.process-block .info-card__label {
  margin-bottom: var(--sp-5);
}

.process-steps {
  display: flex;
  flex-direction: column;
  gap: 0;
  border-left: 1px solid var(--c-border-subtle);
  padding-left: var(--sp-6);
  margin-left: var(--sp-2);
}

.process-steps li {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-4);
  padding: var(--sp-4) 0;
  position: relative;
  border-bottom: 1px solid var(--c-border-subtle);
}

.process-steps li:last-child { border-bottom: none; }

.process-steps li::before {
  content: '';
  position: absolute;
  left: calc(-1 * var(--sp-6) - 1px);
  top: var(--sp-5);
  width: 8px;
  height: 8px;
  background: var(--c-accent);
  border-radius: var(--r-full);
  transform: translateX(-3.5px);
}

.process-step__num {
  font-size: 0.65rem;
  color: var(--c-accent);
  letter-spacing: 0.06em;
  flex-shrink: 0;
  margin-top: 0.2rem;
}

.process-steps li div strong {
  font-size: 0.88rem;
  color: var(--c-text-primary);
  display: block;
  margin-bottom: var(--sp-1);
}

.process-steps li div p {
  font-size: 0.84rem;
  line-height: 1.65;
}

/* Respondent Stat */
.respondent-stat {
  display: flex;
  justify-content: center;
  margin-top: var(--sp-10);
}

.respondent-stat__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--sp-2);
  background: var(--c-base);
  border: 1px solid var(--c-border);
  border-radius: var(--r-xl);
  padding: var(--sp-6) var(--sp-12);
  box-shadow: var(--shadow-card), var(--shadow-accent);
}

.respondent-num {
  font-size: clamp(2.5rem, 5vw, 3.5rem);
  font-weight: 500;
  color: var(--c-accent);
  line-height: 1;
  letter-spacing: -0.03em;
}

.respondent-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--c-text-tertiary);
}

/* ─────────────────────────────────────────
   17. CHARTS GRID
───────────────────────────────────────── */
.charts-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-6);
  margin-bottom: var(--sp-12);
}

/* Chart card — double-bezel */
.chart-card {
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-card);
  border-radius: var(--r-xl);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.35s var(--ease-out),
              transform 0.35s var(--ease-spring);
}

.chart-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.chart-card__inner {
  background: var(--c-surface-3);
  border: 1px solid var(--c-border-subtle);
  border-radius: calc(var(--r-xl) - 0.5rem);
  padding: var(--sp-6);
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.04);
}

.chart-title {
  font-size: 1rem;
  color: var(--c-text-primary);
  margin-bottom: var(--sp-1);
}

.chart-subtitle {
  font-size: 0.68rem;
  color: var(--c-text-tertiary);
  letter-spacing: 0.06em;
  margin-bottom: var(--sp-5);
}

.chart-wrap {
  position: relative;
  width: 100%;
  max-width: 320px;
  margin-inline: auto;
}

.chart-wrap--bar {
  max-width: 100%;
}

/* ─────────────────────────────────────────
   18. STAT CARDS
───────────────────────────────────────── */
.stat-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-5);
  margin-bottom: var(--sp-12);
}

.stat-card {
  border-radius: var(--r-2xl);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.35s var(--ease-out),
              transform 0.35s var(--ease-spring);
}

.stat-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-3px);
}

.stat-card--red {
  background: var(--c-surface-2);
  border: 1px solid rgba(180,68,68,0.22);
}

.stat-card--green {
  background: var(--c-surface-2);
  border: 1px solid rgba(56,160,108,0.22);
}

.stat-card__inner {
  border-radius: calc(var(--r-2xl) - 0.5rem);
  padding: var(--sp-8) var(--sp-8);
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.04);
}

.stat-card--red .stat-card__inner {
  background: rgba(180, 68, 68, 0.08);
  border: 1px solid rgba(180,68,68,0.12);
}

.stat-card--green .stat-card__inner {
  background: rgba(56, 160, 108, 0.08);
  border: 1px solid rgba(56,160,108,0.12);
}

.stat-card__number {
  display: flex;
  align-items: baseline;
  gap: 0.1em;
  margin-bottom: var(--sp-4);
}

.stat-number {
  font-size: clamp(3rem, 8vw, 5rem);
  font-weight: 500;
  letter-spacing: -0.04em;
  line-height: 1;
}

.stat-card--red  .stat-number { color: var(--c-red-text); }
.stat-card--green .stat-number { color: var(--c-green-text); }

.stat-pct {
  font-family: var(--font-mono);
  font-size: clamp(1.2rem, 3vw, 2rem);
  font-weight: 400;
}

.stat-card--red  .stat-pct { color: var(--c-red-text); }
.stat-card--green .stat-pct { color: var(--c-green-text); }

.stat-desc {
  font-size: 1rem;
  line-height: 1.6;
  color: var(--c-text-primary);
  margin-bottom: var(--sp-4);
}

.stat-desc strong { font-weight: 700; }

.stat-scenario {
  display: block;
  font-size: 0.68rem;
  letter-spacing: 0.06em;
  color: var(--c-text-tertiary);
}

/* ─────────────────────────────────────────
   19. SVG DIAGRAM CARDS
───────────────────────────────────────── */
.svg-diagram-plain {
  margin-bottom: var(--sp-6);
  padding: var(--sp-4) 0;
}

.svg-diagram-card {
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-card);
  border-radius: var(--r-2xl);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
  margin-bottom: var(--sp-8);
  transition: box-shadow 0.35s var(--ease-out);
}

.svg-diagram-card:hover { box-shadow: var(--shadow-hover); }

.svg-diagram-card__inner {
  background: var(--c-surface-3);
  border: 1px solid var(--c-border-subtle);
  border-radius: calc(var(--r-2xl) - 0.5rem);
  padding: var(--sp-8) var(--sp-6);
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.04);
}

.diagram-title {
  font-size: 1rem;
  color: var(--c-text-primary);
  margin-bottom: var(--sp-5);
  text-align: center;
}

.svg-wrap {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.demand-svg,
.positioning-svg {
  width: 100%;
  height: auto;
  min-width: 320px;
}

.diagram-caption {
  font-size: 0.78rem;
  line-height: 1.6;
  color: var(--c-text-tertiary);
  text-align: center;
  margin-top: var(--sp-5);
  font-style: italic;
  max-width: 680px;
  margin-inline: auto;
}

/* ─────────────────────────────────────────
   20. ANALYSIS PROSE
───────────────────────────────────────── */
.analysis-prose {
  padding: var(--sp-2) 0 var(--sp-4);
}

.analysis-intro {
  font-size: 0.875rem;
  color: var(--c-text-tertiary);
  font-style: italic;
  margin-bottom: var(--sp-5);
  user-select: text;
  cursor: auto;
}

.analysis-p {
  font-size: 0.9rem;
  line-height: 1.78;
  color: var(--c-text-secondary);
  user-select: text;
  cursor: auto;
}

.analysis-p + .analysis-p {
  margin-top: var(--sp-5);
}

.def-item {
  padding: var(--sp-4) 0;
}

.def-item + .def-item {
  border-top: 1px solid rgba(201, 137, 58, 0.1);
}

.def-item + .analysis-p {
  margin-top: var(--sp-5);
}

.def-term {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--c-text-primary);
  margin-bottom: var(--sp-1);
}

.def-body {
  font-size: 0.875rem;
  line-height: 1.7;
  color: var(--c-text-secondary);
  user-select: text;
  cursor: auto;
}

.subsection-divider {
  border: none;
  border-top: 1px solid rgba(201, 137, 58, 0.22);
  margin: var(--sp-8) 0;
}

/* ─────────────────────────────────────────
   21. CHALLENGES GRID
───────────────────────────────────────── */
.challenges-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-3);
  margin-bottom: var(--sp-6);
}

.challenge-card {
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-card);
  border-radius: var(--r-lg);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.3s var(--ease-out),
              transform 0.3s var(--ease-spring);
}

.challenge-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateX(3px);
}

.challenge-card__inner {
  background: var(--c-surface-3);
  border: 1px solid var(--c-border-subtle);
  border-radius: calc(var(--r-lg) - 0.4rem);
  padding: var(--sp-4) var(--sp-5);
  display: flex;
  gap: var(--sp-4);
  align-items: flex-start;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.04);
}

.challenge-num {
  font-size: 0.65rem;
  color: var(--c-accent);
  letter-spacing: 0.06em;
  flex-shrink: 0;
  margin-top: 0.1rem;
}

.challenge-card__inner p {
  font-size: 0.88rem;
  line-height: 1.65;
  user-select: text;
}

/* ─────────────────────────────────────────
   22. CONCLUSION SECTION
───────────────────────────────────────── */
.conclusion-block {
  margin-bottom: var(--sp-12);
}

.concl-label {
  display: block;
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--c-text-tertiary);
  margin-bottom: var(--sp-8);
}

.concl-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--sp-10);
}

.concl-item {
  display: grid;
  grid-template-columns: 3rem 1fr;
  gap: var(--sp-6);
  align-items: start;
}

.concl-num {
  font-size: 1.75rem;
  font-weight: 500;
  color: var(--c-accent);
  line-height: 1;
  padding-top: 0.1rem;
}

.concl-text {
  font-size: 0.95rem;
  line-height: 1.75;
  color: var(--c-text-secondary);
  user-select: text;
  cursor: auto;
}

/* ─────────────────────────────────────────
   23. RECOMMENDATIONS GRID
───────────────────────────────────────── */
.recommendations-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-4);
}

.rec-card {
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-card);
  border-radius: var(--r-xl);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
  transition: box-shadow 0.35s var(--ease-out),
              transform 0.35s var(--ease-spring);
}

.rec-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.rec-card__inner {
  background: var(--c-base);
  border: 1px solid var(--c-border-subtle);
  border-radius: calc(var(--r-xl) - 0.5rem);
  padding: var(--sp-6);
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.03);
  height: 100%;
}

.rec-num {
  font-size: 0.65rem;
  color: var(--c-accent);
  letter-spacing: 0.08em;
  display: block;
  margin-bottom: var(--sp-3);
}

.rec-card__inner h4 {
  margin-bottom: var(--sp-3);
  font-size: 0.95rem;
}

.rec-card__inner p {
  font-size: 0.86rem;
  line-height: 1.68;
  user-select: text;
}

/* ─────────────────────────────────────────
   24. REFERENCES SECTION
───────────────────────────────────────── */
.references-card {
  background: var(--c-base);
  border: 1px solid var(--c-border-card);
  border-radius: var(--r-2xl);
  padding: var(--sp-2);
  box-shadow: var(--shadow-card);
  margin-bottom: var(--sp-8);
}

.references-card__inner {
  background: var(--c-surface-2);
  border: 1px solid var(--c-border-subtle);
  border-radius: calc(var(--r-2xl) - 0.5rem);
  padding: var(--sp-8);
  box-shadow: inset 0 1px 1px rgba(255,255,255,0.04);
}

.reference-list {
  display: flex;
  flex-direction: column;
  gap: var(--sp-5);
  margin-top: var(--sp-5);
  padding-left: var(--sp-5);
  list-style: decimal;
  list-style-position: outside;
}

.reference-list li {
  font-size: 0.88rem;
  line-height: 1.7;
  color: var(--c-text-secondary);
  user-select: text;
  padding-left: var(--sp-2);
}

.reference-list li em { font-style: italic; }

.reference-list li::marker {
  color: var(--c-accent);
  font-family: var(--font-mono);
  font-size: 0.75rem;
}

/* Evidence Placeholder */
.evidence-placeholder {
  background: var(--c-base);
  border: 1px dashed var(--c-border);
  border-radius: var(--r-xl);
  padding: var(--sp-2);
}

.evidence-placeholder__inner {
  background: var(--c-surface-2);
  border: 1px dashed var(--c-border-subtle);
  border-radius: calc(var(--r-xl) - 0.5rem);
  padding: var(--sp-8);
  text-align: center;
}

.evidence-note {
  font-size: 0.88rem;
  color: var(--c-text-tertiary);
  line-height: 1.6;
}

/* ─────────────────────────────────────────
   25. FOOTER
───────────────────────────────────────── */
.site-footer {
  background: #080706;
  border-top: 1px solid var(--c-border-subtle);
  padding-block: var(--sp-12);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-8);
  margin-bottom: var(--sp-8);
}

.footer-brand {
  font-size: 0.82rem;
  color: var(--c-accent);
  letter-spacing: 0.04em;
  margin-bottom: var(--sp-2);
}

.footer-sub {
  font-size: 0.8rem;
  color: var(--c-text-tertiary);
  line-height: 1.6;
}

.footer-label {
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--c-accent);
  margin-bottom: var(--sp-3);
}

.footer-members {
  display: flex;
  flex-direction: column;
  gap: var(--sp-1);
}

.footer-members li {
  font-size: 0.84rem;
  color: var(--c-text-secondary);
  user-select: text;
}

.footer-col p {
  font-size: 0.84rem;
  color: var(--c-text-secondary);
  line-height: 1.65;
  user-select: text;
}

.footer-bottom {
  padding-top: var(--sp-6);
  border-top: 1px solid var(--c-border-subtle);
}

.footer-note {
  font-size: 0.68rem;
  letter-spacing: 0.04em;
  color: var(--c-text-tertiary);
  line-height: 1.6;
}

/* ─────────────────────────────────────────
   26. SCROLL ANIMATIONS (data-animate)
───────────────────────────────────────── */
[data-animate] {
  opacity: 0;
  transform: translateY(28px) scale(0.97);
  transition: opacity 0.75s var(--ease-spring),
              transform 0.75s var(--ease-spring);
}

[data-animate].is-visible {
  opacity: 1;
  transform: none;
}

/* Stagger for children within a data-animate-children container */
[data-animate-children] > [data-animate]:nth-child(1) { transition-delay: 0ms; }
[data-animate-children] > [data-animate]:nth-child(2) { transition-delay: 80ms; }
[data-animate-children] > [data-animate]:nth-child(3) { transition-delay: 160ms; }
[data-animate-children] > [data-animate]:nth-child(4) { transition-delay: 240ms; }
[data-animate-children] > [data-animate]:nth-child(5) { transition-delay: 320ms; }
[data-animate-children] > [data-animate]:nth-child(6) { transition-delay: 400ms; }

/* Disable animation on reduced motion */
@media (prefers-reduced-motion: reduce) {
  [data-animate] {
    opacity: 1;
    transform: none;
    transition: none;
  }
  .scroll-line { animation: none; }
}

/* No-transition utility (used by JS to skip animation for in-view elements on load) */
.no-transition {
  transition: none !important;
}

/* ─────────────────────────────────────────
   27. FOCUS STATES (accessibility)
───────────────────────────────────────── */
:focus-visible {
  outline: 2px solid var(--c-accent);
  outline-offset: 3px;
  border-radius: var(--r-sm);
}

/* ─────────────────────────────────────────
   28. RESPONSIVE — 640px (tablet-small)
───────────────────────────────────────── */
@media (min-width: 640px) {
  .info-grid {
    grid-template-columns: 1fr 1fr;
  }

  .stat-cards {
    grid-template-columns: 1fr 1fr;
  }

  .method-grid {
    grid-template-columns: 1fr 1fr;
  }

  .challenges-grid {
    grid-template-columns: 1fr 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }

  .group-members {
    gap: var(--sp-2);
  }
}

/* ─────────────────────────────────────────
   29. RESPONSIVE — 768px (tablet)
───────────────────────────────────────── */
@media (min-width: 768px) {
  .nav-links {
    display: flex;
  }

  .hamburger {
    display: none;
  }

  .charts-grid {
    grid-template-columns: 1fr 1fr;
  }

  .charts-grid .chart-card:first-child {
    grid-column: 1 / -1;
  }

  .recommendations-grid {
    grid-template-columns: 1fr 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr 1fr;
  }
}

/* ─────────────────────────────────────────
   30. RESPONSIVE — 1024px (desktop)
───────────────────────────────────────── */
@media (min-width: 1024px) {
  .info-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .method-grid {
    grid-template-columns: repeat(4, 1fr);
  }

  .charts-grid {
    grid-template-columns: 1fr 1fr 1fr;
  }

  .charts-grid .chart-card:first-child {
    grid-column: auto;
  }

  .challenges-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .recommendations-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  h1 {
    font-size: clamp(3rem, 5.5vw, 4.5rem);
  }

  .section--intro .section-body {
    padding-block: var(--sp-24);
  }
}

/* ─────────────────────────────────────────
   31. RESPONSIVE — 1280px (wide)
───────────────────────────────────────── */
@media (min-width: 1280px) {
  .container {
    padding-inline: var(--sp-8);
  }

  .section {
    padding-block: var(--sp-32);
  }

  .section-body {
    padding-block: var(--sp-24);
  }
}